document.write( "Question 800786: For their field studies in marine ecology, a group of students rented a boat for P360. However, seven students had to withdraw from the group and as a result, the share of each of the remaining students was increased by P21.00. How many students were there in the original group? \n" ); document.write( "
Algebra.Com's Answer #483286 by ankor@dixie-net.com(22740)![]() ![]() You can put this solution on YOUR website! For their field studies in marine ecology, a group of students rented a boat for P360. \n" ); document.write( "However, seven students had to withdraw from the group and as a result, the share of each of the remaining students was increased by P21.00. \n" ); document.write( " How many students were there in the original group? \n" ); document.write( ": \n" ); document.write( "Let x = no. of students in original group \n" ); document.write( ": \n" ); document.write( " \n" ); document.write( "then \n" ); document.write( " \n" ); document.write( ": \n" ); document.write( "Actual price - original price = 21 \n" ); document.write( " \n" ); document.write( "multiply by x(x-7) to clear the denominators, resulting in: \n" ); document.write( "360x - 360(x-7) = 21x(x-7) \n" ); document.write( "360x - 360x + 2520 = 21x^2 - 147x \n" ); document.write( "Combine as a quadratic equation \n" ); document.write( "0 = 21x^2 - 147x - 2520 \n" ); document.write( "simplify, divide by 21 \n" ); document.write( "x^2 - 7x - 120 = 0 \n" ); document.write( "Factors to \n" ); document.write( "(x-15) (x+8) = 0 \n" ); document.write( "the positive solution is all we want here \n" ); document.write( "x = 15 students originally \n" ); document.write( ": \n" ); document.write( ": \n" ); document.write( "See if that checks out, find the cost per student \n" ); document.write( "360/8 = 45 (actual) \n" ); document.write( "360/15= 24 (originally) \n" ); document.write( "------------ \n" ); document.write( "diff: 21 \n" ); document.write( " |